The air treating device of the present invention is activated by memory-shaped metal alloy elements. These memory-shaped metal alloy elements cause a diaphragm to be displaced thereby moving air. Fluid pumps using diaphragms which are actuated by memory-shaped metal alloy elements are known, such as disclosed in U.S. Pat. No. 3,606,592. This patent discloses a single diaphragm being mounted within a housing and when actuable causes liquid displacement through ports on both sides of the housing as the diaphragm moves thereacross due to the heating and cooling of its memory-shaped metal alloy elements. It is also known to use electrically actuated contractible elements to act as a pump in a prosthetic device for a biological system, such as disclosed in U.S. Pat. No. 3,827,426. The present invention uses this type of concept for displacing a pair of spaced apart diaphragm to act as a bellows, and more specifically a compressor which in turn cools and displaces surrounding air about the bellows which is mounted in a bellows box.
There is a need to provide an air treating device which is capable of cooling large volumes of air using minimal power in a light-weight application and wherein the device may be packaged in a very compact form for use in various applications, such as a military application to provide effective cooling of air pilot suits. This need has led to the development of the air treating device of the present invention.
Prior art compressors have included those having piezoelectric diaphragms, in which a piezoelectric ceramic material, such as barium titanate, is alternately pulsed to provide a direct mechanical output. While satisfactory for some applications, these devices suffer from the drawback of relatively low displacements of the piezoelectric material, leading to high power consumption, poor efficiencies, and complexity of design in the power circuit and valving, hence rendering such devices unsatisfactory for compressor or pump applications.